Pneumatic powered autoinjector

• US 20030233070A1
• Filed: 11/08/2002
• Published: 12/18/2003
• Est. Priority Date: 11/09/2001
• Status: Active Grant

• Current Assignee: Pedro E De La Serna, Scott J. Gilbert
• Original Assignee: Pedro E De La Serna, Scott J. Gilbert
• Inventors: Gilbert, Scott J., De La Serna, Pedro E.
• Granted Patent: US 7,654,983 B2
• Time in Patent Office: Days
• US Class Current: 604/141
• CPC Class Codes: A61K 9/0004 Osmotic delivery systems; Sustained release driven by osmosis, thermal energy or gas
• CPC Class Codes: A61M 5/2053 Media being expelled from injector by pressurised fluid or vacuum for infusion A61M5/145, A61M5/155
• CPC Class Codes: A61M 5/282 by compression of deformable ampoule or carpule wall
• CPC Class Codes: A61M 5/326 Fully automatic sleeve extension, i.e. in which triggering of the sleeve does not require a deliberate action by the user
• CPC Class Codes: A61M 5/46 having means for controlling depth of insertion
• CPC Class Codes: A61M 5/482 Varying injection pressure, e.g. by varying speed of injection
• CPC Class Codes: F16K 17/30 spring-loaded
• CPC Class Codes: G05D 7/0133 within the flow-path

Abstract

The present invention provides a pneumatic injector that includes a pressurized gas source, an actuator, a driver, and a dispenser. The dispenser of the injector includes a reservoir for containing a desired amount of a chosen medicament and a needle, such as a hypodermic needle, suitable for subcutaneous, intramuscular, or intra-articular delivery of the chosen medicament. The actuator actuates the transmission of pressurized gas from the pressurized gas source to the driver, and as pressurized gas is delivered to the driver, the driver exerts at least an injection force. The injection force is of sufficient magnitude to expel a chosen medicament through the needle of the dispenser within a desired amount of time. Advantageously, the design of the injector of the present invention is extremely flexible, allowing the injector to be designed to deliver a wide range of medicaments in virtually any human or veterinary context calling for the injection of the subcutaneous, intramuscular, or intra-articular injection of medicament.

Claims

1. A device for injecting a viscous medicament comprising a needle suitable for injecting the medicament, wherein the gauge of the needle is equal to or greater than about 21 gauge and the device is configured to drive the viscous medicament through the needle with sufficient force to cause injection of the medicament.

2. The device of claim 1, further comprising a pressurized gas source, an actuator, a driver, and a dispenser, wherein the pressurized gas source, the driver, and the dispenser are configured to inject the viscous medicament through the needle upon triggering the actuator.

3. The device of claim 1, wherein the viscous medicament has a viscosity greater than about 5 poise.

4. The device of claim 1, wherein the viscous medicament has a viscosity greater than about 10 poise.

5. The device of claim 1, wherein the viscous medicament has a viscosity greater than about 50 poise.

6. The device of claim 1, wherein the viscous medicament has a viscosity greater than about 100 poise.

7. The device of claim 2, wherein the driver comprises a multistage piston configured to exert at least a first force and a second force against the dispenser.

8. The device of claim 2, wherein the driver comprises a multistage piston configured to exert a first force and a second force against the dispenser, the second force being greater than the first force.

9. The device of claim 8, wherein the multistage piston is configured such that the first force is less than or equal to about 7 lbs and the second force is sufficient to inject the viscous medicament through the needle.

10. The device of claim 1, wherein the gauge of the needle ranges from about 27 gauge to about 31 gauge.

11. The device of claim 1, wherein the device is configured to inject up to about 0.5 cc of the viscous medicament through the needle within about 10 seconds.

12. The device of claim 1, wherein the device is configured to inject up to about 0.5 cc of the viscous medicament through the needle within about 5 seconds.

13. The device of claim 2, wherein the dispenser comprises a reservoir and the needle and the pressurized gas source, multistage piston, and dispenser are configured to inject up to about 0.5 cc of the viscous medicament through the needle within about 10 seconds

14. The device of claim 13, wherein the pressurized gas source, multistage piston, and dispenser are configured to expel up to about 0.5 cc of the viscous medicament through the needle within about 5 seconds.

15. A method for injecting a viscous medicament, the method comprising:

providing a viscous medicament;

providing a needle for injecting the viscous medicament, the needle having a needle gauge that is equal to or greater than about 21 gauge; and

injecting the viscous medicament through the needle.

16. The method according to claim 15, wherein providing the viscous medicament comprises providing a medicament exhibiting a viscosity equal to or greater than about 5 poise.

17. The method according to claim 15, wherein providing the viscous medicament comprises providing a medicament exhibiting a viscosity equal to or greater than about 10 poise.

18. The method according to claim 15, wherein providing the viscous medicament comprises providing a medicament exhibiting a viscosity equal to or greater than about 50 poise.

19. The method according to claim 15, wherein providing the viscous medicament comprises providing a medicament exhibiting a viscosity equal to or greater than about 100 poise.

20. The method according to claim 15, wherein providing the needle comprises providing a needle having a needle gauge equal to or greater than about 27 gauge.

21. The method according to claim 15, wherein providing the needle comprises providing a needle having a needle gauge equal to about 31 gauge.

22. A device for injecting a medicament comprising:

a trigger;

a dispenser comprising a reservoir containing the medicament and a needle for injecting the medicament; and

a driver comprising a multistage piston, the device for injecting the medicament being configured such that, upon actuation of the trigger, the multistage piston exerts at least a first force and a second force against the dispenser.

23. The device of claim 22, further comprising a pressurized gas source and wherein the device is configured such that actuation of the trigger causes pressurized gas from the pressurized gas source to act against the multistage piston.

24. The device of claim 22, wherein the multistage piston of the device is configured to exert a first force that is less than a second force.

25. The device of claim 24, wherein the multistage piston of the device is configured such that the first force is exerted prior to exertion of the second force.

26. The device of claim 22, wherein each stage of the multistage piston is characterized by a different surface area.